Fix hint text color to align with latest Material spec

Bug: 30756246
Change-Id: I5063cc81b8ffad6fb46465c1622bd0083380bd49
diff --git a/core/res/res/color/hint_foreground_material_dark.xml b/core/res/res/color/hint_foreground_material_dark.xml
index 77883d9..5cc9559 100644
--- a/core/res/res/color/hint_foreground_material_dark.xml
+++ b/core/res/res/color/hint_foreground_material_dark.xml
@@ -15,6 +15,10 @@
 -->
 
 <selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:state_enabled="true"
+          android:state_pressed="true"
+          android:alpha="@dimen/hint_pressed_alpha_material_dark"
+          android:color="@color/foreground_material_dark" />
     <item android:alpha="@dimen/hint_alpha_material_dark"
           android:color="@color/foreground_material_dark" />
 </selector>
diff --git a/core/res/res/color/hint_foreground_material_light.xml b/core/res/res/color/hint_foreground_material_light.xml
index 99168fd..f7465e0 100644
--- a/core/res/res/color/hint_foreground_material_light.xml
+++ b/core/res/res/color/hint_foreground_material_light.xml
@@ -15,6 +15,10 @@
 -->
 
 <selector xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:state_enabled="true"
+          android:state_pressed="true"
+          android:alpha="@dimen/hint_pressed_alpha_material_light"
+          android:color="@color/foreground_material_light" />
     <item android:alpha="@dimen/hint_alpha_material_light"
           android:color="@color/foreground_material_light" />
 </selector>
diff --git a/core/res/res/values/colors_material.xml b/core/res/res/values/colors_material.xml
index a864cf3..92426c6 100644
--- a/core/res/res/values/colors_material.xml
+++ b/core/res/res/values/colors_material.xml
@@ -61,7 +61,10 @@
     <color name="secondary_text_default_material_dark">#b3ffffff</color>
 
     <item name="hint_alpha_material_dark" format="float" type="dimen">0.50</item>
-    <item name="hint_alpha_material_light" format="float" type="dimen">0.54</item>
+    <item name="hint_alpha_material_light" format="float" type="dimen">0.38</item>
+
+    <item name="hint_pressed_alpha_material_dark" format="float" type="dimen">0.70</item>
+    <item name="hint_pressed_alpha_material_light" format="float" type="dimen">0.54</item>
 
     <item name="disabled_alpha_material_light" format="float" type="dimen">0.26</item>
     <item name="disabled_alpha_material_dark" format="float" type="dimen">0.30</item>